1
|
Gillespie CD, Yates A, Hughes M, Ewins K, McMahon G, Hynes J, Murphy MC, Galligan M, Vencken S, Alih E, Varden J, Donnelly J, Bolster F, Rowan M, Foley S, NíAinle F, MacMahon PJ. Validating the safety of low-dose CTPA in pregnancy: results from the OPTICA (Optimised CT Pulmonary Angiography in Pregnancy) Study. Eur Radiol 2024; 34:4864-4873. [PMID: 38296849 DOI: 10.1007/s00330-024-10593-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/23/2023] [Accepted: 12/27/2023] [Indexed: 02/02/2024]
Abstract
BACKGROUND Pulmonary embolism (PE) is a leading cause of pregnancy-related mortality. CT pulmonary angiogram (CTPA) is the first-line advanced imaging modality for suspected PE in pregnancy at institutes offering low-dose techniques; however, a protocol balancing safety with low dose remains undefined. The wide range of CTPA doses reported in pregnancy suggests a lack of confidence in implementing low-dose techniques in this group. PURPOSE To define and validate the safety, radiation dose and image quality of a low-dose CTPA protocol optimised for pregnancy. MATERIALS AND METHODS The OPTICA study is a prospective observational study. Pregnant study participants with suspected PE underwent the same CTPA protocol between May 2018 and February 2022. The primary outcome, CTPA safety, was judged by the reference standard; the 3-month incidence of venous thromboembolism (VTE) in study participants with a negative index CTPA. Secondary outcomes defined radiation dose and image quality. Absorbed breast, maternal effective and fetal doses were estimated by Monte-Carlo simulation on gestation-matched phantoms. Image quality was assessed by signal-to-noise and contrast-to-noise ratios and a Likert score for pulmonary arterial enhancement. RESULTS A total of 116 CTPAs were performed in 113 pregnant women of which 16 CTPAs were excluded. PE was diagnosed on 1 CTPA and out-ruled in 99. The incidence of recurrent symptomatic VTE was 0.0% (one-sided 95% CI, 2.66%) at follow-up. The mean absorbed breast dose was 2.9 ± 2.1mGy, uterine/fetal dose was 0.1 ± 0.2mGy and maternal effective dose was 1.4 ± 0.9mSv. Signal-to-noise ratio (SNR) was 11.9 ± 3.7. Contrast-to-noise ratio (CNR) was 10.4 ± 3.5. CONCLUSION The OPTICA CTPA protocol safely excluded PE in pregnant women across all trimesters, with low fetal and maternal radiation. CLINICAL RELEVANCE OPTICA (Optimised CT Pulmonary Angiography in Pregnancy) is the first prospective study to define the achievable radiation dose, image-quality and safety of a low-dose CT pulmonary angiogram protocol optimised for pregnancy (NCT04179487). It provides the current benchmark for safe and achievable CT pulmonary angiogram doses in the pregnant population. KEY POINTS • Despite the increased use of CT pulmonary angiogram in pregnancy, an optimised low-dose protocol has not been defined and reported doses in pregnancy continue to vary widely. • The OPTICA (Optimised CT Pulmonary Angiography in Pregnancy) study prospectively defines the achievable dose, image quality and safety of a low-dose CT pulmonary angiogram protocol using widely available technology. • OPTICA provides a benchmark for safe and achievable CT pulmonary angiogram doses in the pregnant population.
Collapse
Affiliation(s)
- Ciara D Gillespie
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland.
| | - Andrew Yates
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
| | - Mark Hughes
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
| | - Karl Ewins
- Department of Haematology, Mater Misericordiae University Hospital, Dublin, D07 R2WY, Ireland
| | - Gabriella McMahon
- Department of Obstetrics, Rotunda Hospital, Dublin, D01 P5W9, Ireland
| | - John Hynes
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
| | - Mark C Murphy
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
| | - Marie Galligan
- Clinical Research Centre, School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Sebastian Vencken
- Clinical Research Centre, School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Ekele Alih
- Clinical Research Centre, School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - John Varden
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
| | - Jennifer Donnelly
- Department of Obstetrics, Rotunda Hospital, Dublin, D01 P5W9, Ireland
- School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Ferdia Bolster
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
- School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Michael Rowan
- Department of Medical Physics, St James Hospital, Dublin, D08 NHY1, Ireland
| | - Shane Foley
- Radiography & Diagnostic Imaging, School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Fionnuala NíAinle
- Department of Haematology, Mater Misericordiae University Hospital, Dublin, D07 R2WY, Ireland
- School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Peter J MacMahon
- Department of Radiology, Mater Misericordiae University Hospital, Whitty Building, North Circular Road, Dublin 7, Dublin, D07 R2WY, Ireland
- School of Medicine, University College Dublin, Dublin, D04 V1W8, Ireland
| |
Collapse
|
2
|
Santos Armentia E, Martín Noguerol T, Silva Priegue N, Delgado Sánchez-Gracián C, Trinidad López C, Prada González R. Strengths, weaknesses, opportunities, and threat analysis of dual-energy CT in head and neck imaging. RADIOLOGIA 2022; 64:333-347. [DOI: 10.1016/j.rxeng.2022.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/19/2022] [Indexed: 11/29/2022]
|
3
|
Santos Armentia E, Martín-Noguerol T, Silva Priegue N, Delgado Sánchez-Gracián C, Trinidad López C, Prada González R. Análisis de las fortalezas, oportunidades, debilidades y amenazas de la tomografía computarizada de doble energía en el diagnóstico por la imagen de la cabeza y el cuello. RADIOLOGIA 2022. [DOI: 10.1016/j.rx.2022.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
4
|
Aldosari S, Sun Z. A Systematic Review of Double Low-dose CT Pulmonary Angiography in Pulmonary Embolism. Curr Med Imaging 2020; 15:453-460. [PMID: 32008552 DOI: 10.2174/1573405614666180813120619] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 07/20/2018] [Accepted: 07/31/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND The aim of this study is to perform a systematic review of the feasibility and clinical application of double low-dose CT pulmonary angiography (CTPA) in the diagnosis of patients with suspected pulmonary embolism. DISCUSSION A total of 13 studies were found to meet selection criteria reporting both low radiation dose (70 or 80 kVp versus 100 or 120 kVp) and low contrast medium dose CTPA protocols. Lowdose CTPA resulted in radiation dose reduction from 29.6% to 87.5% in 12 studies (range: 0.4 to 23.5 mSv), while in one study, radiation dose was increased in the dual-energy CT group when compared to the standard 120 kVp group. CTPA with use of low contrast medium volume (range: 20 to 75 ml) was compared to standard CTPA (range: 50 to 101 ml) in 12 studies with reduction between 25 and 67%, while in the remaining study, low iodine concentration was used with 23% dose reduction achieved. Quantitative assessment of image quality (in terms of signal-to-noise ratio and contrast-to-noise ratio) showed that low-dose CTPA was associated with higher, lower and no change in image quality in 3, 3 and 6 studies, respectively when compared to the standard CTPA protocol. The subjective assessment indicated similar image quality in 11 studies between low-dose and standard CTPA groups, and improved image quality in 1 study with low-dose CTPA. CONCLUSION This review shows that double low-dose CTPA is feasible in the diagnosis of pulmonary embolism with significant reductions in both radiation and contrast medium doses, without compromising diagnostic image quality.
Collapse
Affiliation(s)
- Sultan Aldosari
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Australia
| | - Zhonghua Sun
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Australia
| |
Collapse
|
5
|
Sauter AP, Shapira N, Kopp FK, Aichele J, Bodden J, Knipfer A, Rummeny EJ, Noël PB. CTPA with a conventional CT at 100 kVp vs. a spectral-detector CT at 120 kVp: Comparison of radiation exposure, diagnostic performance and image quality. Eur J Radiol Open 2020; 7:100234. [PMID: 32420413 PMCID: PMC7215101 DOI: 10.1016/j.ejro.2020.100234] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/10/2020] [Accepted: 04/18/2020] [Indexed: 12/15/2022] Open
Abstract
With SD-CT, increased radiation exposure is not present. In the current study, CTDIvol was lower with SD-CT than with C-CT, even when 100 kVp was used for the latter. With SD-CT, higher levels of diagnostic performance and image quality can be achieved. SD-CT may be the system of choice due to the availability of spectral data and thus additional image information.
Purpose To compare CT pulmonary angiographies (CTPAs) as well as phantom scans obtained at 100 kVp with a conventional CT (C-CT) to virtual monochromatic images (VMI) obtained with a spectral detector CT (SD-CT) at equivalent dose levels as well as to compare the radiation exposure of both systems. Material and Methods In total, 2110 patients with suspected pulmonary embolism (PE) were examined with both systems. For each system (C-CT and SD-CT), imaging data of 30 patients with the same mean CT dose index (4.85 mGy) was used for the reader study. C-CT was performed with 100 kVp and SD-CT was performed with 120 kVp; for SD-CT, virtual monochromatic images (VMI) with 40, 60 and 70 keV were calculated. All datasets were evaluated by three blinded radiologists regarding image quality, diagnostic confidence and diagnostic performance (sensitivity, specificity). Contrast-to-noise ratio (CNR) for different iodine concentrations was evaluated in a phantom study. Results CNR was significantly higher with VMI at 40 keV compared to all other datasets. Subjective image quality as well as sensitivity and specificity showed the highest values with VMI at 60 keV and 70 keV. Hereby, a significant difference to 100 kVp (C-CT) was found for image quality. The highest sensitivity was found using VMI at 60 keV with a sensitivity of more than 97 % for all localizations of PE. For diagnostic confidence and subjective contrast, highest values were found with VMI at 40 keV. Conclusion Higher levels of diagnostic performance and image quality were achieved for CPTAs with SD-CT compared to C-CT given similar dose levels. In the clinical setting SD-CT may be the modality of choice as additional spectral information can be obtained.
Collapse
Key Words
- BMI, body mass index
- C-CT, conventional spiral CT
- CNR, contrast-to-noise ratio
- CT, computed tomography
- CTDIVOL, volume-weighted CT dose index
- CTPA, CT pulmonary angiography
- Computed tomography angiography
- DE-CT, dual-Energy CT
- DLP, dose length product
- DS-CT, dual-Source CT
- ED, effective dose
- HU, Hounsfield Units
- IQ, image quality
- PE, pulmonary embolism
- Patient safety
- Pulmonary embolism
- ROI, region of interest
- Radiation exposure
- Radiologic
- SD-CT, spectral-detector CT
- Technology
- VMI, virtual monochromatic images
- kVp, peak kilovoltage
- keV, kilo-electronvolt
Collapse
Affiliation(s)
- Andreas P Sauter
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Nadav Shapira
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA.,Philips Healthcare, Haifa, Israel
| | - Felix K Kopp
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Juliane Aichele
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Jannis Bodden
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Andreas Knipfer
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Ernst J Rummeny
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Peter B Noël
- Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany.,Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| |
Collapse
|
6
|
Dymbe B, Mæland EV, Styve JR, Rusandu A. Individualization of computed tomography protocols for suspected pulmonary embolism: a national investigation of routines. J Int Med Res 2020; 48:300060520918427. [PMID: 32290743 PMCID: PMC7157970 DOI: 10.1177/0300060520918427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Objective Given the extensive use of computed tomography (CT) in radiation-sensitive patients such as pregnant and pediatric patients, and considering the importance of tailoring CT protocols to patient characteristics for both the radiation dose and image quality, this study was performed to investigate the extent to which individualization of CT protocols is practiced across Norway. Methods This cross-sectional study involved collection of CT protocols and administration of a mini-questionnaire to obtain additional information about how CT examinations are individualized. All public hospitals performing CT to detect pulmonary embolism were invited, and 41% participated. Results Tailoring a standard protocol to different patient groups was more common than using dedicated protocols. Most of the available radiation dose-reduction approaches were used. However, implementation of these strategies was not systematic. Children and pregnant patients were examined without using dedicated CT protocols or by using protocol adjustments focusing on radiation dose reduction in 30% and 39% of the hospitals, respectively. Conclusion Practice optimization is needed, especially the development of dedicated CT protocols or guidelines that tailor the existing protocol to pediatric and pregnant patients. Practice might benefit from a more systematic approach to individualization of CT examinations, such as inserting tailoring instructions into CT protocols.
Collapse
Affiliation(s)
- Berit Dymbe
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Elisabeth Vespestad Mæland
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Jorunn Rønhovde Styve
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Albertina Rusandu
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| |
Collapse
|
7
|
Rajiah P, Ciancibello L, Novak R, Sposato J, Landeras L, Gilkeson R. Ultra-low dose contrast CT pulmonary angiography in oncology patients using a high-pitch helical dual-source technology. ACTA ACUST UNITED AC 2020; 25:195-203. [PMID: 31063136 DOI: 10.5152/dir.2019.17498] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
PURPOSE We aimed to determine if the image quality and vascular enhancement are preserved in computed tomography pulmonary angiography (CTPA) studies performed with ultra-low contrast and optimized radiation dose using high-pitch helical mode of a second generation dual source scanner. METHODS We retrospectively evaluated oncology patients who had CTPA on a 128-slice dual-source scanner, with a high-pitch helical mode (3.0), following injection of 30 mL of Ioversal at 4 mL/s with body mass index (BMI) dependent tube potential (80-120 kVp) and current (130-150 mAs). Attenuation, noise, and signal-to-noise ratio (SNR) were measured in multiple pulmonary arteries. Three independent readers graded the images on a 5-point Likert scale for central vascular enhancement (CVE), peripheral vascular enhancement (PVE), and overall quality. RESULTS There were 50 males and 101 females in our study. BMI ranged from 13 to 38 kg/m2 (22.8±4.4 kg/m2). Pulmonary embolism was present in 29 patients (18.9%). Contrast enhancement and SNR were excellent in all the pulmonary arteries (395.3±131.1 and 18.3±5.7, respectively). Image quality was considered excellent by all the readers, with average reader scores near the highest possible score of 5.0 (CVE, 4.83±0.48; PVE, 4.68±0.65; noise/quality, 4.78±0.47). The average radiation dose length product (DLP) was 161±60 mGy.cm. CONCLUSION Using a helical high-pitch acquisition technique, CTPA images of excellent diagnostic quality, including visualization of peripheral segmental/sub-segmental branches can be obtained using an ultra-low dose of iodinated contrast and low radiation dose.
Collapse
Affiliation(s)
- Prabhakar Rajiah
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA;Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Leslie Ciancibello
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| | - Ronald Novak
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA;Rebecca D. Considine Research Institute, Akron Children's Hospital, Akron, Ohio, USA
| | - Jennifer Sposato
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| | - Luis Landeras
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA;Department of Radiology, University of Chicago, Chicago, Illinois, USA
| | - Robert Gilkeson
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| |
Collapse
|
8
|
Bajc M, Lindqvist A. Ventilation/Perfusion SPECT Imaging Diagnosing PE and Other Cardiopulmonary Diseases. Clin Nucl Med 2020. [DOI: 10.1007/978-3-030-39457-8_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
9
|
Forbrig R, Ingrisch M, Stahl R, Winter KS, Reiser M, Trumm CG. Radiation dose and image quality of high-pitch emergency abdominal CT in obese patients using third-generation dual-source CT (DSCT). Sci Rep 2019; 9:15877. [PMID: 31685902 PMCID: PMC6828752 DOI: 10.1038/s41598-019-52454-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 10/17/2019] [Indexed: 01/01/2023] Open
Abstract
In this third-generation dual-source CT (DSCT) study, we retrospectively investigated radiation dose and image quality of portal-venous high-pitch emergency CT in 60 patients (28 female, mean age 56 years) with a body mass index (BMI) ≥ 30 kg/m2. Patients were dichotomized in groups A (median BMI 31.5 kg/m2; n = 33) and B (36.8 kg/m2; n = 27). Volumetric CT dose index (CTDIvol), size-specific dose estimate (SSDE), dose length product (DLP) and effective dose (ED) were assessed. Contrast-to-noise ratio (CNR) and dose-independent figure-of-merit (FOM) CNR were calculated. Subjective image quality was assessed using a five-point scale. Mean values of CTDIvol, SSDE as well as normalized DLP and ED were 7.6 ± 1.8 mGy, 8.0 ± 1.8 mGy, 304 ± 74 mGy * cm and 5.2 ± 1.3 mSv for group A, and 12.6 ± 3.7 mGy, 11.0 ± 2.6 mGy, 521 ± 157 mGy * cm and 8.9 ± 2.7 mSv for group B (p < 0.001). CNR of the liver and spleen as well as each calculated FOM CNR were significantly higher in group A (p < 0.001). Subjective image quality was good in both groups. In conclusion, third-generation abdominal high-pitch emergency DSCT yields good image quality in obese patients. Radiation dose increases in patients with a BMI > 36.8 kg/m2.
Collapse
Affiliation(s)
- Robert Forbrig
- Institute of Neuroradiology, University Hospital, LMU Munich, Munich, Germany.
| | - Michael Ingrisch
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Robert Stahl
- Institute of Neuroradiology, University Hospital, LMU Munich, Munich, Germany
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | | | - Maximilian Reiser
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Christoph G Trumm
- Institute of Neuroradiology, University Hospital, LMU Munich, Munich, Germany
- Institute for Diagnostic and Interventional Radiology, Neuroradiology and Nuclear Medicine, München Klinik Harlaching, Munich, Germany
| |
Collapse
|
10
|
Bajc M, Schümichen C, Grüning T, Lindqvist A, Le Roux PY, Alatri A, Bauer RW, Dilic M, Neilly B, Verberne HJ, Delgado Bolton RC, Jonson B. EANM guideline for ventilation/perfusion single-photon emission computed tomography (SPECT) for diagnosis of pulmonary embolism and beyond. Eur J Nucl Med Mol Imaging 2019; 46:2429-2451. [PMID: 31410539 PMCID: PMC6813289 DOI: 10.1007/s00259-019-04450-0] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/17/2019] [Indexed: 12/18/2022]
Abstract
These guidelines update the previous EANM 2009 guidelines on the diagnosis of pulmonary embolism (PE). Relevant new aspects are related to (a) quantification of PE and other ventilation/perfusion defects; (b) follow-up of patients with PE; (c) chronic PE; and (d) description of additional pulmonary physiological changes leading to diagnoses of left ventricular heart failure (HF), chronic obstructive pulmonary disease (COPD) and pneumonia. The diagnosis of PE should be reported when a mismatch of one segment or two subsegments is found. For ventilation, Technegas or krypton gas is preferred over diethylene triamine pentaacetic acid (DTPA) in patients with COPD. Tomographic imaging with V/PSPECT has higher sensitivity and specificity for PE compared with planar imaging. Absence of contraindications makes V/PSPECT an essential method for the diagnosis of PE. When V/PSPECT is combined with a low-dose CT, the specificity of the test can be further improved, especially in patients with other lung diseases. Pitfalls in V/PSPECT interpretation are discussed. In conclusion, V/PSPECT is strongly recommended as it accurately establishes the diagnosis of PE even in the presence of diseases like COPD, HF and pneumonia and has no contraindications.
Collapse
Affiliation(s)
- Marika Bajc
- Department of Clinical Sciences, Clinical Physiology and Nuclear Medicine, University of Lund, Lund, Sweden.
| | - Carl Schümichen
- University of Rostock, Formerly Clinic for Nuclear Medicine, Rostock, Germany
| | - Thomas Grüning
- Department of Nuclear Medicine, University Hospitals Plymouth, Plymouth, UK
| | - Ari Lindqvist
- Research Unit of Pulmonary Diseases, Clinical Research Institute, HUS Helsinki University Hospital, Helsinki, Finland
| | | | - Adriano Alatri
- Division of Angiology, Heart and Vessel Department, Lausanne University Hospital, Lausanne, Switzerland
| | - Ralf W Bauer
- RNS Gemeinschaftspraxis, Wiesbaden, Germany
- Department of Diagnostic and Interventional Radiology, Goethe University Frankfurt (Main), Frankfurt, Germany
| | - Mirza Dilic
- Clinic of Heart and Blood Vessel Disease, Clinical Center University of Sarajevo, Sarajevo, Bosnia and Herzegovina
| | - Brian Neilly
- Department of Nuclear Medicine, Royal Infirmary, Glasgow, UK
| | - Hein J Verberne
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Roberto C Delgado Bolton
- Department of Diagnostic Imaging (Radiology) and Nuclear Medicine, University Hospital San Pedro and Centre for Biomedical Research of La Rioja (CIBIR), Logroño, La Rioja, Spain
| | - Bjorn Jonson
- Department of Clinical Sciences, Clinical Physiology and Nuclear Medicine, University of Lund, Lund, Sweden
| |
Collapse
|
11
|
Al Hassan DA, Waheed KB, El Sirafy MN, Khattab MA, Al-Hammadi HI, Ibrahim MF, Arulanantham ZJ. Computed tomography pulmonary angiography using high-pitch dual-source scanner technology. Saudi Med J 2019; 40:230-237. [PMID: 30834417 PMCID: PMC6468199 DOI: 10.15537/smj.2019.3.23940] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Objectives: To compare use of ultra-fast high-pitch dual-source free-breathing computed tomography pulmonary angiogram (CTPA) with conventional standard-pitch single-source breath-hold CTPA. Methods: This retrospective comparative study was conducted in Radiology Department at King Fahad Military Medical Complex Dhahran, Saudi Arabia from July 2016 to December 2017. Patients (N=130) were divided into 2 groups, each having 65 consecutive patients; Group-1 (single-source CT) and Group-2 (dual-source CT). Previously treated pulmonary embolism cases, pregnant patients and those with incomplete data were excluded. Image quality was subjectively assessed by 2 readers for adequacy of contrast opacification and pulmonary vessel outline, and presence of artifacts (breathing motion, cardiac pulsation, and contrast related). Scan acquisition times and radiation doses were also compared. Chi-square and t-test were used to determine association. Results: Improved image quality (optimal studies without artifacts 91%) was seen in Group-2 compared to Group-1 (optimal studies without artifacts 75.4%). Also, reduced scan time (1-2 sec.) and radiation dose (mean dose length product (DLP)-248 mGy-cm) were observed in Group-2 compared to Group-1 (scan time- 6.5 sec, mean DLP-375). Results were found significant (p<0.05). Conclusion: High-pitch dual-source CT with free-breathing yields better image quality, reduces image acquisition time and radiation doses.
Collapse
Affiliation(s)
- Donya A Al Hassan
- Department of Radiology, King Fahad Military Medical Complex,Prince Sultan Military College of Health Science, Dhahran, Kingdom of Saudi Arabia. E-mail.
| | - Khawaja B Waheed
- Radiology Department, King Fahad Military Medical Complex, Dhahran, Kingdom of Saudi Arabia. E-mail.
| | | | | | | | | | | |
Collapse
|
12
|
Zucker EJ, Kino A, Schmiedeskamp H, Hinostroza V, Fleischmann D, Chan FP. Feasibility and utility of dual-energy chest CTA for preoperative planning in pediatric pulmonary artery reconstruction. Int J Cardiovasc Imaging 2019; 35:1473-1481. [PMID: 31016501 DOI: 10.1007/s10554-019-01602-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/09/2019] [Indexed: 01/26/2023]
Abstract
The purpose of this study was to assess in pediatric pulmonary artery (PA) reconstruction candidates the feasibility and added utility of preoperative chest computed tomography angiography (CTA) using dual-energy technique, from which perfused blood volume (PBV)/iodine maps can be generated as a surrogate of pulmonary perfusion. Pediatric PA reconstruction patients were prospectively recruited for a new dose-neutral dual-energy CTA protocol. For each case, the severity of anatomic PA obstruction was graded by two pediatric cardiovascular radiologists in consensus using a modified Qanadli index. PBV maps were qualitatively reviewed and auto-segmented using Siemens syngo.via software. Associations between Qanadli scores and PBV were assessed with Spearman correlation (r) and ROC analysis. Effective radiation doses were estimated from dose-length product and ICRP 103 k-factors, using cubic Hermite spline interpolation. 19 patients were recruited with mean (SD) age of 6.0 (5.1), 11 (57.9%) female, 11 (73.7%) anesthetized. Higher QS correlated with lower PBV, both on a whole lung (r = - 0.54, p < 0.001) and lobar (r = - 0.50, p < 0.001) basis. The lung with lowest absolute PBV was predictive of the lung with highest Qanadli score, with AUC of 0.70 (95% CI 0.47-0.93). Qualitatively, PBV maps were heterogeneous, corresponding to multifocal PA stenoses, with decreased iodine content in areas of most severe obstruction. In conclusion, dual-energy chest CTA is feasible for pediatric PA reconstruction candidates. PBV maps show deficits in regions of more severe anatomic obstruction and may serve as a novel biomarker in this population.
Collapse
Affiliation(s)
- Evan J Zucker
- Department of Radiology, Stanford University School of Medicine, 725 Welch Road, Stanford, CA, 94305, USA.
| | - Aya Kino
- Department of Radiology, Stanford University School of Medicine, 725 Welch Road, Stanford, CA, 94305, USA
| | - Heiko Schmiedeskamp
- Siemens Medical Solutions USA, 40 Liberty Boulevard, Malvern, PA, 19355, USA
| | - Virginia Hinostroza
- Department of Radiology, Stanford University School of Medicine, 725 Welch Road, Stanford, CA, 94305, USA
| | - Dominik Fleischmann
- Department of Radiology, Stanford University School of Medicine, 725 Welch Road, Stanford, CA, 94305, USA
| | - Frandics P Chan
- Department of Radiology, Stanford University School of Medicine, 725 Welch Road, Stanford, CA, 94305, USA
| |
Collapse
|
13
|
Radiation exposure related to cardiovascular CT examination: comparison between conventional 64-MDCT and third-generation dual-source MDCT. Radiol Med 2019; 124:753-761. [PMID: 31011995 DOI: 10.1007/s11547-019-01036-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 04/09/2019] [Indexed: 01/02/2023]
|
14
|
Haneder S, Siedek F, Doerner J, Pahn G, Grosse Hokamp N, Maintz D, Wybranski C. Thoracic-abdominal imaging with a novel dual-layer spectral detector CT: intra-individual comparison of image quality and radiation dose with 128-row single-energy acquisition. Acta Radiol 2018; 59:1458-1465. [PMID: 29569933 DOI: 10.1177/0284185118762611] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND A novel, multi-energy, dual-layer spectral detector computed tomography (SDCT) is commercially available now with the vendor's claim that it yields the same or better quality of polychromatic, conventional CT images like modern single-energy CT scanners without any radiation dose penalty. PURPOSE To intra-individually compare the quality of conventional polychromatic CT images acquired with a dual-layer spectral detector (SDCT) and the latest generation 128-row single-energy-detector (CT128) from the same manufacturer. MATERIAL AND METHODS Fifty patients underwent portal-venous phase, thoracic-abdominal CT scans with the SDCT and prior CT128 imaging. The SDCT scanning protocol was adapted to yield a similar estimated dose length product (DLP) as the CT128. Patient dose optimization by automatic tube current modulation and CT image reconstruction with a state-of-the-art iterative algorithm were identical on both scanners. CT image contrast-to-noise ratio (CNR) was compared between the SDCT and CT128 in different anatomic structures. Image quality and noise were assessed independently by two readers with 5-point-Likert-scales. Volume CT dose index (CTDIvol), and DLP were recorded and normalized to 68 cm acquisition length (DLP68). RESULTS The SDCT yielded higher mean CNR values of 30.0% ± 2.0% (26.4-32.5%) in all anatomic structures ( P < 0.001) and excellent scores for qualitative parameters surpassing the CT128 (all P < 0.0001) with substantial inter-rater agreement (κ ≥ 0.801). Despite adapted scan protocols the SDCT yielded lower values for CTDIvol (-10.1 ± 12.8%), DLP (-13.1 ± 13.9%), and DLP68 (-15.3 ± 16.9%) than the CT128 (all P < 0.0001). CONCLUSION The SDCT scanner yielded better CT image quality compared to the CT128 and lower radiation dose parameters.
Collapse
Affiliation(s)
- Stefan Haneder
- Institute of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany
| | - Florian Siedek
- Institute of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany
| | - Jonas Doerner
- Institute of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany
| | - Gregor Pahn
- Philips CT Clinical Science, Hamburg, Germany
| | - Nils Grosse Hokamp
- Institute of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany
| | - David Maintz
- Institute of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany
| | - Christian Wybranski
- Institute of Diagnostic and Interventional Radiology, University Hospital of Cologne, Cologne, Germany
| |
Collapse
|
15
|
Radiation dose and image quality with new protocol in lower extremity computed tomography angiography. Radiol Med 2018; 124:184-190. [PMID: 30478814 DOI: 10.1007/s11547-018-0963-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/18/2018] [Indexed: 02/08/2023]
Abstract
PURPOSE To compare radiation dose and image quality of lower extremity computed tomography angiography (CTA) between cranio-caudal acquisition with single-source CT (SSCT) and flash caudo-cranial acquisition with dual-source CT (DSCT). MATERIALS AND METHODS In this prospective study, 60 patients were randomly assigned to Group A (control) or Group B (experimental) to undergo lower extremity CTA for peripheral obliterative arterial disease. Group A received protocol 1 (P1) with SSCT cranio-caudal acquisition. Group B received protocol (P2) with DSCT flash caudo-cranial acquisition. Intravascular attenuation (IVA), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and image noise were compared. Two radiologists assessed the image quality. Computed tomography volume dose index (CTDIvol) and dose-length product (DLP) were also compared. RESULTS IVA with P2 was higher than with P1 (586.8 ± 140.3 vs. 496.1 ± 129.3 HU, p = 0.011), as was SNR (33.0 ± 11.3 vs. 27.4 ± 12.3; p = 0.042), CNR (30.1 ± 13.3 vs. 24.2 ± 10.3; p = 0.029) and image quality score of small arteries below the knee (3.8 ± 0.2 vs. 3.1 ± 0.2; p = 0.001). Radiation dose was significantly lower in P2 than in P1 with CTDIvol reduction of 40.9% (1.3 ± 0.1 vs. 2.2 ± 0.3 mGy; p = 0.006) and DLP reduction of 42.8% (148.7 ± 21.9 vs 260.2 ± 59.1 mGy * cm; p = 0.018). CONCLUSION Lower extremity CTA with DSCT flash caudo-cranial acquisition allows lower radiation dose with higher IVA, SNR, CNR and better image quality for small arteries below the knee than SSCT cranio-caudal acquisition.
Collapse
|
16
|
Dual-Energy Computed Tomography-Based Iodine Quantitation for Response Evaluation of Lung Cancers to Chemoradiotherapy/Radiotherapy: A Comparison With Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography-Based Positron Emission Tomography/Computed Tomography Response Evaluation Criterion in Solid Tumors. J Comput Assist Tomogr 2018; 42:614-622. [PMID: 29613988 DOI: 10.1097/rct.0000000000000734] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE The objective of this study was to investigate the correlation between dual-energy computed tomography (DECT)-based iodine quantitation and fluorine-18 fluorodeoxyglucose (F-FDG) positron emission tomography (PET)/computed tomography (CT) imaging for response evaluation of lung cancers to treatment. METHODS In this prospective study, a total of 32 pairs of DECT and F-FDG PET/CT imaging acquired consecutively from 13 patients with primary or metastatic lung cancers receiving either radiotherapy alone or chemoradiotherapy were analyzed. Imaging examinations were performed before, immediately, and no later than 6 months after treatment for response evaluation. Iodine-related parameters including the total iodine uptake (TIU) and vital volume (VIV) from DECT and metabolic metrics such as the standardized uptake value normalized to lean body mass (SULpeak), metabolic tumor volume (MTV), and the total lesion glycolysis (TLG) from F-FDG-PET/CT were generated and measured by semiautomatic approaches. Dual-energy CT and PET/CT metrics were calculated and followed up with comparison with response evaluation criteria in solid tumors (RECIST). RESULTS Analysis of pretreatment imaging data revealed a strong correlation between DECT metrics (RECIST, TIU, and VIV) and F-FDG PET/CT metrics (MTV, TLG) with coefficients of R ranging from 0.86 to 0.90 (P < 0.01). With the delivery of treatment, all measured DECT and PET/CT metrics significantly decreased whereas the descending amplitude in RECIST was significantly smaller than that of the remaining parameters (P < 0.05). During follow-up examinations, both metrics followed a similar changing pattern. Overall, strong consistency was found between RECIST, TIU, VIV and SULpeak, MTV, TLG (R covers 0.78-0.96, P < 0.05). CONCLUSIONS Semiautomatic iodine-related quantitation in DECT correlated well with metabolism-based measurements in F-FDG PET/CT, suggesting that DECT-based iodine quantitation might be a feasible substitute for assessment of lung cancer response to chemoradiotherapy/radiotherapy with comparison with F-FDG PET/CT.
Collapse
|
17
|
Wortman JR, Sodickson AD. Pearls, Pitfalls, and Problems in Dual-Energy Computed Tomography Imaging of the Body. Radiol Clin North Am 2018; 56:625-640. [PMID: 29936951 DOI: 10.1016/j.rcl.2018.03.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dual-energy computed tomography (DECT) is an exciting technology that is increasing in routine use and has the potential for significant clinical impact. With the advancement of DECT, it is important for radiologists to be aware of potential challenges with DECT acquisition and postprocessing, and to have a basic knowledge of unique artifacts and diagnostic pitfalls that can occur when interpreting DECT scans and DECT postprocessed images. This article serves as a practical overview of potential problems and diagnostic pitfalls associated with DECT, and steps that can be taken to avoid them.
Collapse
Affiliation(s)
- Jeremy R Wortman
- Division of Emergency Radiology, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
| | - Aaron D Sodickson
- Division of Emergency Radiology, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA
| |
Collapse
|
18
|
Parakh A, Macri F, Sahani D. Dual-Energy Computed Tomography: Dose Reduction, Series Reduction, and Contrast Load Reduction in Dual-Energy Computed Tomography. Radiol Clin North Am 2018; 56:601-624. [PMID: 29936950 DOI: 10.1016/j.rcl.2018.03.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Evolution in computed tomography technology and image reconstruction have significantly changed practice. Dual energy computed tomography is being increasingly adopted owing to benefits of material separation, quantification, and improved contrast-to-noise ratio. The radiation dose can match that from single energy computed tomography. Spectral information derived from a polychromatic x-ray beam at different energies yields in image reconstructions that reduce the number of phases in a multiphasic examination and decrease the absolute amount of contrast media. This increased analytical and image processing capability provides new avenues for addressing radiation dose and iodine exposure concerns.
Collapse
Affiliation(s)
- Anushri Parakh
- Department of Radiology, Abdominal Imaging Division, Massachusetts General Hospital, White 270, 55 Fruit Street, Boston, MA 02114, USA
| | - Francesco Macri
- Department of Radiology, Abdominal Imaging Division, Massachusetts General Hospital, White 270, 55 Fruit Street, Boston, MA 02114, USA; Department of Radiology, University Hospital of Nimes, Place di Pr Debre, Nimes 30029, France
| | - Dushyant Sahani
- Department of Radiology, Abdominal Imaging Division, Massachusetts General Hospital, White 270, 55 Fruit Street, Boston, MA 02114, USA.
| |
Collapse
|
19
|
Li X, Chen GZ, Zhao YE, Schoepf UJ, Albrecht MH, Bickford MW, Gu HF, Zhang LJ, Lu GM. Radiation Optimized Dual-source Dual-energy Computed Tomography Pulmonary Angiography: Intra-individual and Inter-individual Comparison. Acad Radiol 2017; 24:13-21. [PMID: 27789203 DOI: 10.1016/j.acra.2016.09.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 09/11/2016] [Accepted: 09/14/2016] [Indexed: 11/28/2022]
Abstract
OBJECTIVES This study aimed to intra-individually and inter-individually compare image quality, radiation dose, and diagnostic accuracy of dual-source dual-energy computed tomography pulmonary angiography (CTPA) protocols in patients with suspected pulmonary embolism (PE). METHODS Thirty-three patients with suspected PE underwent initial and follow-up dual-energy CTPA at 80/Sn140 kVp (group A) or 100/Sn140 kVp (group B), which were assigned based on tube voltages. Subjective and objective CTPA image quality and lung perfusion map image quality were evaluated. Diagnostic accuracies of CTPA and perfusion maps were assessed by two radiologists independently. Effective dose (ED) was calculated and compared. RESULTS Mean computed tomography (CT) values of pulmonary arteries were higher in group A than group B (P = .006). There was no difference in signal-to-noise ratio and contrast-to-noise ratio between the two groups (both P > .05). Interobserver agreement for evaluating subjective image quality of CTPA and color-coded perfusion images was either good (κ = 0.784) or excellent (κ = 0.887). Perfusion defect scores and diagnostic accuracy of CTPA showed no difference between both groups (both P > .05). Effective dose of group A was reduced by 45.8% compared to group B (P < .001). CONCLUSIONS Second-generation dual-source dual-energy CTPA with 80/Sn140 kVp allows for sufficient image quality and diagnostic accuracy for detecting PE while substantially reducing radiation dose.
Collapse
Affiliation(s)
- Xie Li
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Guo Zhong Chen
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Yan E Zhao
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - U Joseph Schoepf
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina
| | - Moritz H Albrecht
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina
| | - Matthew W Bickford
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina
| | - Hai Feng Gu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China.
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China.
| |
Collapse
|
20
|
Use of low tube voltage and low contrast agent concentration yields good image quality for aortic CT angiography. Clin Radiol 2016; 71:1313.e5-1313.e10. [DOI: 10.1016/j.crad.2016.07.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 07/20/2016] [Accepted: 07/25/2016] [Indexed: 11/22/2022]
|
21
|
State-of-the-Art Pulmonary CT Angiography for Acute Pulmonary Embolism. AJR Am J Roentgenol 2016; 208:495-504. [PMID: 27897042 DOI: 10.2214/ajr.16.17202] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Pulmonary CT angiography (CTA) is the imaging modality of choice in suspected acute pulmonary embolism (PE). Current pulmonary CTA techniques involve ever lower doses of contrast medium and radiation along with advanced postprocessing applications to enhance image quality, diagnostic accuracy, and provide added value in patient management. The objective of this article is to summarize these current developments and discuss the appropriate use of state-of-the-art pulmonary CTA. CONCLUSION Pulmonary CTA is well established as a fast and reliable means of excluding or diagnosing PE. Continued developments in CT system hardware and postprocessing techniques will allow incremental reductions in radiation and contrast material requirements while improving image quality. Advances in risk stratification and prognostication from pulmonary CTA examinations should further refine its clinical value while minimizing the potential harm from overutilization and overdiagnosis.
Collapse
|
22
|
Wolfe JM. Use-inspired basic research in medical image perception. Cogn Res Princ Implic 2016; 1:17. [PMID: 28180168 PMCID: PMC5256442 DOI: 10.1186/s41235-016-0019-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/08/2016] [Indexed: 12/21/2022] Open
Abstract
This journal is dedicated to "use-inspired basic research" where a problem in the world shapes the hypotheses for a study in the laboratory. This brief review presents several examples of "use-inspired basic research" in the area of medical image perception. These are cases where the field of radiology raises an interesting issue in visual cognition. Basic research on those issues may then lead to proposals to improve performance on clinical tasks in medical image perception. Of the six examples given here, the first three ask essentially perceptual questions: How can stereopsis improve medical image perception? How shall we assess the tradeoff between radiation dose and image quality? How does the choice of colors change the interpretation of medical images? The second three examples address attentional issues in those aspects of radiology that can be described as visual search problems: Can eye tracking help us understand errors in radiologic search? What happens if the number of targets in an image is unknown? What happens if, as in radiology screening programs, the target of search is very rare?
Collapse
Affiliation(s)
- Jeremy M. Wolfe
- Ophthalmology & Radiology, Harvard Medical School, 64 Sidney St. Suite 170, Cambridge, MA 02139-4170 USA
- Visual Attention Lab, Department of Surgery, Brigham & Women’s Hospital, 64 Sidney St. Suite 170, Cambridge, MA 02139-4170 USA
| |
Collapse
|
23
|
High-pitch Helical Dual-source Computed Tomographic Pulmonary Angiography: Comparing Image Quality in Inspiratory Breath-hold and During Free Breathing. J Thorac Imaging 2016; 31:56-62. [PMID: 26447868 DOI: 10.1097/rti.0000000000000173] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The purpose of this study was to compare qualitative and quantitative image parameters of dual-source high-pitch helical computed tomographic pulmonary angiography (CTPA) in breath-holding (BH) versus free-breathing (FB) patients. MATERIALS AND METHODS Ninety-nine consented patients (61 female individuals; mean age±SD, 49±18.7 y) were randomized into BH (n=45) versus FB (n=54) high-pitch helical CTPA. Patient characteristics and CTPA radiation doses were analyzed. Two readers assessed for pulmonary embolism (PE), transient interruption of contrast, and respiratory and cardiac motion. The readers used a subjective 3-point scale to rate the pulmonary artery opacification and lung parenchymal appearance. A single reader assessed mean pulmonary artery signal intensity, noise, contrast, signal to noise ratio, and contrast to noise ratio. RESULTS PE was diagnosed in 16% BH and 19% FB patients. CTPAs of both groups were of excellent or acceptable quality for PE evaluation and of similar mean radiation doses (1.3 mSv). Transient interruption of contrast was seen in 5/45 (11%) BH and 5/54 (9%) FB patients (not statistically significant, P=0.54). No statistically significant difference was noted in cardiac, diaphragmatic, and lung parenchymal motion. Lung parenchymal assessment was excellent in all cases, except for 5/54 (9%) motion-affected FB cases with acceptable quality (statistically significant, P=0.03). No CTPA was considered nondiagnostic by any of the readers. No objective image quality differences were noted between both groups (P>0.05). CONCLUSIONS High-pitch helical CTPA acquired during BH or in FB yields comparable image quality for the diagnosis of PE and lung pathology, with low radiation exposure. Only a modest increase in lung parenchymal artifacts is encountered in FB high-pitch helical CTPA.
Collapse
|
24
|
Lorsakul A, Fakhri GE, Worstell W, Ouyang J, Rakvongthai Y, Laine AF, Li Q. Numerical observer for atherosclerotic plaque classification in spectral computed tomography. J Med Imaging (Bellingham) 2016; 3:035501. [PMID: 27429999 PMCID: PMC4940624 DOI: 10.1117/1.jmi.3.3.035501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 06/20/2016] [Indexed: 11/14/2022] Open
Abstract
Spectral computed tomography (SCT) generates better image quality than conventional computed tomography (CT). It has overcome several limitations for imaging atherosclerotic plaque. However, the literature evaluating the performance of SCT based on objective image assessment is very limited for the task of discriminating plaques. We developed a numerical-observer method and used it to assess performance on discrimination vulnerable-plaque features and compared the performance among multienergy CT (MECT), dual-energy CT (DECT), and conventional CT methods. Our numerical observer was designed to incorporate all spectral information and comprised two-processing stages. First, each energy-window domain was preprocessed by a set of localized channelized Hotelling observers (CHO). In this step, the spectral image in each energy bin was decorrelated using localized prewhitening and matched filtering with a set of Laguerre-Gaussian channel functions. Second, the series of the intermediate scores computed from all the CHOs were integrated by a Hotelling observer with an additional prewhitening and matched filter. The overall signal-to-noise ratio (SNR) and the area under the receiver operating characteristic curve (AUC) were obtained, yielding an overall discrimination performance metric. The performance of our new observer was evaluated for the particular binary classification task of differentiating between alternative plaque characterizations in carotid arteries. A clinically realistic model of signal variability was also included in our simulation of the discrimination tasks. The inclusion of signal variation is a key to applying the proposed observer method to spectral CT data. Hence, the task-based approaches based on the signal-known-exactly/background-known-exactly (SKE/BKE) framework and the clinical-relevant signal-known-statistically/background-known-exactly (SKS/BKE) framework were applied for analytical computation of figures of merit (FOM). Simulated data of a carotid-atherosclerosis patient were used to validate our methods. We used an extended cardiac-torso anthropomorphic digital phantom and three simulated plaque types (i.e., calcified plaque, fatty-mixed plaque, and iodine-mixed blood). The images were reconstructed using a standard filtered backprojection (FBP) algorithm for all the acquisition methods and were applied to perform two different discrimination tasks of: (1) calcified plaque versus fatty-mixed plaque and (2) calcified plaque versus iodine-mixed blood. MECT outperformed DECT and conventional CT systems for all cases of the SKE/BKE and SKS/BKE tasks (all [Formula: see text]). On average of signal variability, MECT yielded the SNR improvements over other acquisition methods in the range of 46.8% to 65.3% (all [Formula: see text]) for FBP-Ramp images and 53.2% to 67.7% (all [Formula: see text]) for FBP-Hanning images for both identification tasks. This proposed numerical observer combined with our signal variability framework is promising for assessing material characterization obtained through the additional energy-dependent attenuation information of SCT. These methods can be further extended to other clinical tasks such as kidney or urinary stone identification applications.
Collapse
Affiliation(s)
- Auranuch Lorsakul
- Massachusetts General Hospital, Division of Nuclear Medicine and Molecular Imaging, Gordon Center for Medical Imaging, 55 Fruit Street, White 427, Boston, Massachusetts 02114, United States
- Columbia University, Department of Biomedical Engineering, 1210 Amsterdam Avenue, New York, New York 10027, United States
| | - Georges El Fakhri
- Massachusetts General Hospital, Division of Nuclear Medicine and Molecular Imaging, Gordon Center for Medical Imaging, 55 Fruit Street, White 427, Boston, Massachusetts 02114, United States
- Harvard Medical School, Department of Radiology, 25 Shattuck Street, Boston, Massachusetts 02115, United States
| | - William Worstell
- PhotoDiagnostic System Inc., 85 Swanson Road, Boxborough, Massachusetts 01719, United States
| | - Jinsong Ouyang
- Massachusetts General Hospital, Division of Nuclear Medicine and Molecular Imaging, Gordon Center for Medical Imaging, 55 Fruit Street, White 427, Boston, Massachusetts 02114, United States
- Harvard Medical School, Department of Radiology, 25 Shattuck Street, Boston, Massachusetts 02115, United States
| | - Yothin Rakvongthai
- Massachusetts General Hospital, Division of Nuclear Medicine and Molecular Imaging, Gordon Center for Medical Imaging, 55 Fruit Street, White 427, Boston, Massachusetts 02114, United States
- Chulalongkorn University, Department of Radiology, Faculty of Medicine, 1873 Rama 4 Road, Pathumwan, Bangkok 10330, Thailand
| | - Andrew F. Laine
- Columbia University, Department of Biomedical Engineering, 1210 Amsterdam Avenue, New York, New York 10027, United States
| | - Quanzheng Li
- Massachusetts General Hospital, Division of Nuclear Medicine and Molecular Imaging, Gordon Center for Medical Imaging, 55 Fruit Street, White 427, Boston, Massachusetts 02114, United States
- Harvard Medical School, Department of Radiology, 25 Shattuck Street, Boston, Massachusetts 02115, United States
| |
Collapse
|
25
|
Systematic Comparison of Reduced Tube Current Protocols for High-pitch and Standard-pitch Pulmonary CT Angiography in a Large Single-center Population. Acad Radiol 2016; 23:619-27. [PMID: 26905455 DOI: 10.1016/j.acra.2016.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/15/2015] [Accepted: 01/10/2016] [Indexed: 11/23/2022]
Abstract
RATIONALE AND OBJECTIVES Benefits of iterative reconstruction (IR) algorithms combined with dose-reduction techniques have been shown at computed tomography pulmonary angiography (CTPA) in several medium to small patient collectives. In this study, we performed a systematic comparison of image quality to combinations of reduced tube current (RC) and IR for both standard-pitch (SP) single-source and high-pitch (HP) dual-source CTPA in a large, single-center population. MATERIALS AND METHODS Three hundred eighty-two consecutive patients (October 2010 through December 2012) received clinically indicated CTPA with one of four consecutively changed protocols: (1) HPSC: 180 mAs, weighted filtered back projection, pitch = 3; (2) HPRC: 90 mAs, IR, pitch = 3; (3) SPSC: 180 mAs, weighted filtered back projection, pitch = 1.2; and (4) HPRC: 90 mAs, IR, pitch = 1.2. Tube potential was 100 kV. Vascular attenuation and standardized signal-to-noise ratio (sSNR) were measured in the pulmonary trunk (sSNRPT) and on segmental artery level (sSNRS1, sSNRS10). Dose-length-product was recorded per series. Two independent investigators rated image quality. Kolmogorov-Smirnov test, Kruskal-Wallis test, and kappa statistics were used for statistical analysis. Median values are presented per group. RESULTS Image quality was consistent between all groups (observer 1: P = 0.118; observer 2: P = 0.122). Inter-reader consistency was very good (κ = 0.866, P < 0.001). Dose-length-product was significantly reduced in HP and RC groups (P < 0.001 for each; SPSC: 139.5 mGycm; HPRC: 92 mGycm; SPSC: 211 mGycm; HPRC: 137 mGycm). sSNR was comparable (sSNRPT overall: P = 0.052; sSNRS1 overall: P = 0.161; and sSNRS10 overall: P = 0.259). CONCLUSIONS Substantial dose reduction can be within a routine clinical setting without quantifiable loss of image quality either by HP pulmonary angiography or by a combination of IR and RC in either HP or SP acquisition.
Collapse
|
26
|
Beeres M, Bucher AM, Wichmann JL, Frellesen C, Scholtz JE, Albrecht M, Bodelle B, Nour-Eldin NEA, Lee C, Kaup M, Vogl TJ, Gruber-Rouh T. Improved visual delineation of the intimal flap in Stanford type A and B dissections at 3rd generation dual-source high-pitch CT angiography. Radiol Med 2016; 121:573-9. [PMID: 27100720 DOI: 10.1007/s11547-016-0634-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 03/14/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Evaluation of the intimal flap visibility comparing 2nd and 3rd generation dual-source high-pitch CT. METHODS Twenty-five consecutive patients with aortic dissection underwent CT angiography on a second and third generation dual-source CT scanner using prospective ECG-gated high-pitch dual-source CT acquisition mode. Contrast material, saline flush and flow rate were kept equal for optimum comparability. The visibility of the intimal flap as well as the delineation of the different vascular structures was evaluated. RESULTS In 3rd generation dual-source high-pitch CT we could show a significant improvement of intimal flap visibility in aortic dissection. Especially, the far end of the dissection membrane could be better evaluated in 3rd generation high-pitch CT, reaching statistical significance (P < 0.01). CONCLUSION 3rd Generation high-pitch CT angiography shows a better delineation of the aortic intimal flap in a small patient cohort, especially in the far ends of the dissection membrane. This might be due to higher tube power in this CT generation. However, to generalise these findings larger trials are needed.
Collapse
Affiliation(s)
- Martin Beeres
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Andreas M Bucher
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Julian L Wichmann
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Claudia Frellesen
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Jan E Scholtz
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Moritz Albrecht
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Boris Bodelle
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Nour-Eldin A Nour-Eldin
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.,Department of Diagnostic and Interventional Radiology, Cairo University Hospital, Cairo, Egypt
| | - Clara Lee
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Moritz Kaup
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Thomas J Vogl
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Tatjana Gruber-Rouh
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Haus 23C UG, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| |
Collapse
|
27
|
Sabel BO, Buric K, Karara N, Thierfelder KM, Dinkel J, Sommer WH, Meinel FG. High-Pitch CT Pulmonary Angiography in Third Generation Dual-Source CT: Image Quality in an Unselected Patient Population. PLoS One 2016; 11:e0146949. [PMID: 26872262 PMCID: PMC4752234 DOI: 10.1371/journal.pone.0146949] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 12/22/2015] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To investigate the feasibility of high-pitch CT pulmonary angiography (CTPA) in 3rd generation dual-source CT (DSCT) in unselected patients. METHODS Forty-seven patients with suspected pulmonary embolism underwent high-pitch CTPA on a 3rd generation dual-source CT scanner. CT dose index (CTDIvol) and dose length product (DLP) were obtained. Objective image quality was analyzed by calculating signal-to-noise-ratio (SNR) and contrast-to-noise ratio (CNR). Subjective image quality on the central, lobar, segmental and subsegmental level was rated by two experienced radiologists. RESULTS Median CTDI was 8.1 mGy and median DLP was 274 mGy*cm. Median SNR was 32.9 in the central and 31.9 in the segmental pulmonary arteries. CNR was 29.2 in the central and 28.2 in the segmental pulmonary arteries. Median image quality was "excellent" in central and lobar arteries and "good" in subsegmental arteries according to both readers. Segmental arteries varied between "excellent" and "good". Image quality was non-diagnostic in one case (2%), beginning in the lobar arteries. Thirteen patients (28%) showed minor motion artifacts. CONCLUSIONS In third-generation dual-source CT, high-pitch CTPA is feasible for unselected patients. It yields excellent image quality with minimal motion artifacts. However, compared to standard-pitch cohorts, no distinct decrease in radiation dose was observed.
Collapse
Affiliation(s)
- Bastian O. Sabel
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Kristijan Buric
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Nora Karara
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Kolja M. Thierfelder
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Julien Dinkel
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Wieland H. Sommer
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - Felix G. Meinel
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| |
Collapse
|
28
|
Low-Voltage, High-Pitch Computerized Tomography Angiography of the Infrarenal Aorta and Lower Extremity Vessels: Assessment of Radiation Dose, Image Quality With Hybrid Iterative Reconstruction, and Efficacy of Test Injection Using a Monitoring Scan at Knee Level. J Comput Assist Tomogr 2016; 40:402-8. [PMID: 26854413 DOI: 10.1097/rct.0000000000000365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Our aim was to assess image quality and radiation dose of low-voltage high-pitch computed tomography angiography of the infrarenal aorta and lower extremities and evaluate the efficacy of test injection technique using a monitoring scan at knee level. METHODS A total of 60 patients with suspected peripheral arterial disease were divided into 2 groups: group 1 (30 patients, 80 kVp, high pitch [3.2], and hybrid iterative reconstruction [sinogram-affirmed iterative reconstruction]) and group 2 (30 patients, 120 kVp, low pitch [1.0], and filtered back projection reconstruction). The test injection technique at knee level was used to determine the scan delay time in group 1. The image quality and radiation exposure were compared. RESULTS There were significant differences between the 2 groups in mean (SD) arterial attenuation (80 vs 120 kVp: 507.78 [103.01] vs 317.54 [62.03] Hounsfield units, P < 0.001), mean (SD) signal-to-noise ratio (51.04 [20.29] vs 34.66 [9.94], P < 0.001), and contrast-to-noise ratio (44.83 [17.93] vs 28.26 [9.60], P < 0.001). No difference in subjective image quality was found between the 2 groups (all P > 0.05). The imaging time was significantly shorter in group 1 (2.70 [0.11] vs 14.65 [0.90s], P < 0.001). The mean (SD) effective dose was significantly lower in the 80 kVp group (0.76 [0.06] vs 4.29 [0.63] mSv, P < 0.001). CONCLUSIONS The 80-kVp high-pitch computed tomography angiography of the lower limbs using sinogram-affirmed iterative reconstruction yields reduction of radiation exposure as well as obtains acceptable image quality if acquisition protocols are used in conjunction with the test injection technique using monitoring scan at knee level to determine the delay time.
Collapse
|
29
|
White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 2. J Comput Assist Tomogr 2016; 40:846-850. [DOI: 10.1097/rct.0000000000000539] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
30
|
70-kVp High-pitch Computed Tomography Pulmonary Angiography with 40 mL Contrast Agent: Initial Experience. Acad Radiol 2015; 22:1562-70. [PMID: 26432073 DOI: 10.1016/j.acra.2015.08.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/25/2015] [Accepted: 08/23/2015] [Indexed: 12/11/2022]
Abstract
RATIONALE AND OBJECTIVES To assess image quality, radiation dose, and diagnostic accuracy of 70-kVp high-pitch computed tomography pulmonary angiography (CTPA) using 40 mL contrast agent and sinogram affirmed iterative reconstruction (SAFIRE) compared to 100-kVp CTPA using 60 mL contrast agent and filtered back projection. MATERIALS AND METHODS Eighty patients underwent CTPA at either 70 kVp (group A, n = 40; 3.2 pitch, 40 mL contrast medium, and SAFIRE) or 100 kVp (group B, n = 40; 1.2 pitch, 60 mL contrast medium, and filtered back projection). Signal-to-noise ratio and contrast-to-noise ratio were calculated. Subjective image quality was evaluated using a five-grade scale, and diagnostic accuracy was assessed. Radiation doses were compared. RESULTS Computed tomography values, signal-to-noise ratio, and contrast-to-noise ratio of pulmonary arteries were higher in group A compared to group B (all P < 0.001). Subjective image quality showed no difference between the two groups (P = 0.559) with good interobserver agreement (κ = 0.647). No difference was found regarding diagnostic accuracy between the two groups (P > 0.05). The effective dose for group A was lower by 80% compared to group B (P < 0.001). CONCLUSIONS 70-kVp high-pitch CTPA with reduced contrast media and SAFIRE provides comparable image quality and substantial radiation dose savings compared to a routine CTPA protocol.
Collapse
|
31
|
Gill MK, Vijayananthan A, Kumar G, Jayarani K, Ng KH, Sun Z. Use of 100 kV versus 120 kV in computed tomography pulmonary angiography in the detection of pulmonary embolism: effect on radiation dose and image quality. Quant Imaging Med Surg 2015; 5:524-33. [PMID: 26435916 DOI: 10.3978/j.issn.2223-4292.2015.04.04] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE To determine the effective radiation dose and image quality resulting from 100 versus 120 kilovoltage (kV) protocols among patients referred for computed tomography pulmonary angiography (CTPA). METHODS Sixty-six patients with clinical suspicion of pulmonary embolism (PE) were prospectively enrolled. Two CTPA protocols (group A: n=33, 100 kV/115 mAs; group B: n=33, 120 kV/90 mAs) were compared. Two experienced radiologists assessed image quality in terms of diagnostic performance and effect of artefacts. Image quality parameters [CT attenuation, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR)] and effective radiation dose between the two protocols were compared. RESULTS The contrast enhancement in central and peripheral pulmonary arteries was significantly higher in group A than in group B (P<0.001) with the identical SNR (P=0.26), whereas the CNR was significantly higher in group A than in group B (P<0.001). The effective radiation dose for the 100 and 120 kV scans was 3.2 and 6.8 mSv, respectively. CONCLUSIONS Reducing the tube voltage from 120 to 100 kV in CTPA allows a significant reduction of radiation dose without significant loss of diagnostic image quality.
Collapse
Affiliation(s)
- Maninderpal Kaur Gill
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; 2 University of Malaya Research Imaging Centre (UMRIC), University of Malaya, Kuala Lumpur, Malaysia ; 3 Department of Medical Radiation Sciences, Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| | - Anushya Vijayananthan
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; 2 University of Malaya Research Imaging Centre (UMRIC), University of Malaya, Kuala Lumpur, Malaysia ; 3 Department of Medical Radiation Sciences, Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| | - Gnana Kumar
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; 2 University of Malaya Research Imaging Centre (UMRIC), University of Malaya, Kuala Lumpur, Malaysia ; 3 Department of Medical Radiation Sciences, Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| | - Kasthoori Jayarani
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; 2 University of Malaya Research Imaging Centre (UMRIC), University of Malaya, Kuala Lumpur, Malaysia ; 3 Department of Medical Radiation Sciences, Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| | - Kwan-Hoong Ng
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; 2 University of Malaya Research Imaging Centre (UMRIC), University of Malaya, Kuala Lumpur, Malaysia ; 3 Department of Medical Radiation Sciences, Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| | - Zhonghua Sun
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; 2 University of Malaya Research Imaging Centre (UMRIC), University of Malaya, Kuala Lumpur, Malaysia ; 3 Department of Medical Radiation Sciences, Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia
| |
Collapse
|
32
|
Lung Nodule Detection by Microdose CT Versus Chest Radiography (Standard and Dual-Energy Subtracted). AJR Am J Roentgenol 2015; 204:727-35. [DOI: 10.2214/ajr.14.12921] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
33
|
Meinel FG, Nance JW, Harris BS, De Cecco CN, Costello P, Schoepf UJ. Radiation risks from cardiovascular imaging tests. Circulation 2015; 130:442-5. [PMID: 25070551 DOI: 10.1161/circulationaha.113.005340] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Felix G Meinel
- From the Department of Radiology and Radiological Science (F.G.M., J.W.N., B.S.H., C.N.D.C., P.C., U.J.S.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, Charleston; Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (F.G.M.); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD (J.W.N.); and Departments of Radiological Sciences, Oncology, and Pathology, University of Rome "Sapienza"--Polo Pontino, Latina, Italy (C.N.D.C.)
| | - John W Nance
- From the Department of Radiology and Radiological Science (F.G.M., J.W.N., B.S.H., C.N.D.C., P.C., U.J.S.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, Charleston; Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (F.G.M.); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD (J.W.N.); and Departments of Radiological Sciences, Oncology, and Pathology, University of Rome "Sapienza"--Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Brett S Harris
- From the Department of Radiology and Radiological Science (F.G.M., J.W.N., B.S.H., C.N.D.C., P.C., U.J.S.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, Charleston; Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (F.G.M.); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD (J.W.N.); and Departments of Radiological Sciences, Oncology, and Pathology, University of Rome "Sapienza"--Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Carlo N De Cecco
- From the Department of Radiology and Radiological Science (F.G.M., J.W.N., B.S.H., C.N.D.C., P.C., U.J.S.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, Charleston; Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (F.G.M.); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD (J.W.N.); and Departments of Radiological Sciences, Oncology, and Pathology, University of Rome "Sapienza"--Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Philip Costello
- From the Department of Radiology and Radiological Science (F.G.M., J.W.N., B.S.H., C.N.D.C., P.C., U.J.S.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, Charleston; Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (F.G.M.); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD (J.W.N.); and Departments of Radiological Sciences, Oncology, and Pathology, University of Rome "Sapienza"--Polo Pontino, Latina, Italy (C.N.D.C.)
| | - U Joseph Schoepf
- From the Department of Radiology and Radiological Science (F.G.M., J.W.N., B.S.H., C.N.D.C., P.C., U.J.S.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, Charleston; Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (F.G.M.); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD (J.W.N.); and Departments of Radiological Sciences, Oncology, and Pathology, University of Rome "Sapienza"--Polo Pontino, Latina, Italy (C.N.D.C.).
| |
Collapse
|
34
|
Sun Z, Al Moudi M, Cao Y. CT angiography in the diagnosis of cardiovascular disease: a transformation in cardiovascular CT practice. Quant Imaging Med Surg 2014; 4:376-96. [PMID: 25392823 DOI: 10.3978/j.issn.2223-4292.2014.10.02] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 09/26/2014] [Indexed: 12/11/2022]
Abstract
Computed tomography (CT) angiography represents the most important technical development in CT imaging and it has challenged invasive angiography in the diagnostic evaluation of cardiovascular abnormalities. Over the last decades, technological evolution in CT imaging has enabled CT angiography to become a first-line imaging modality in the diagnosis of cardiovascular disease. This review provides an overview of the diagnostic applications of CT angiography (CTA) in cardiovascular disease, with a focus on selected clinical challenges in some common cardiovascular abnormalities, which include abdominal aortic aneurysm (AAA), aortic dissection, pulmonary embolism (PE) and coronary artery disease. An evidence-based review is conducted to demonstrate how CT angiography has changed our approach in the diagnosis and management of cardiovascular disease. Radiation dose reduction strategies are also discussed to show how CT angiography can be performed in a low-dose protocol in the current clinical practice.
Collapse
Affiliation(s)
- Zhonghua Sun
- 1 Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University, Perth, 6102, Western Australia, Australia ; 2 Department of Medical Imaging and Nuclear Medicine, King Saud Medical City, Riyadh, Saudi Arabia ; 3 Department of Medical Imaging, Shandong Medical College, Jinan 276000, China
| | - Mansour Al Moudi
- 1 Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University, Perth, 6102, Western Australia, Australia ; 2 Department of Medical Imaging and Nuclear Medicine, King Saud Medical City, Riyadh, Saudi Arabia ; 3 Department of Medical Imaging, Shandong Medical College, Jinan 276000, China
| | - Yan Cao
- 1 Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University, Perth, 6102, Western Australia, Australia ; 2 Department of Medical Imaging and Nuclear Medicine, King Saud Medical City, Riyadh, Saudi Arabia ; 3 Department of Medical Imaging, Shandong Medical College, Jinan 276000, China
| |
Collapse
|
35
|
The effect of the section thickness used for 2- and 3-dimensional quantification of dual-energy perfusion computed tomography. J Comput Assist Tomogr 2014; 38:979-84. [PMID: 25229200 DOI: 10.1097/rct.0000000000000148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To retrospectively investigate the effect of the section thickness used for quantifying dual-energy perfusion computed tomography (DEpCT) during 2- and 3-dimensional evaluation. METHODS Sixty-six patients (22 males and 44 females; mean age, 59.3 years) suspected of having an acute pulmonary embolism underwent DEpCT, and 15patients were diagnosed to have intrapulmonary clots (IPCs). Two-dimensional DEpCT images were reconstructed into various section thicknesses from 1 to 10 mm at the main pulmonary artery, and the ratios of the low attenuation area (LAA) ranging from 1 to 5 HU (%LAA5) and 10 HU (%LAA10) on DEpCT were compared with the relative areas of the lung with attenuation coefficients lower than -950 HU (RA-950) using the lung CT images of each section thickness. Three-dimensional values of DEpCT were reconstructed with 3 different section thicknesses (1, 3, and 10 mm) and were analyzed for the presence of IPC burden using the factors suggesting IPC burden, including the right/left ventricular diameter ratio and CT obstruction index. RESULTS The mean attenuation and image noise were decreased as the section thickness increased. In the 2-dimensional analysis, the %LAA5 and %LAA10 had the smallest value at 1-mm section, and DEpCT with thinner sections had a correlation with the RA-950 (r = 0.22-0.23, P < 0.05). The 3-dimensional values of DEpCT reconstructed with a 1- or 3-mm section thickness had a correlation with the CT obstruction index (r = 0.52-0.59, P < 0.05) and right/left ventricular diameter ratio (r = 0.60-0.68, P < 0.01). CONCLUSIONS The thinner images should be used for 2- and 3-dimensional quantification of DEpCT.
Collapse
|
36
|
Lu GM, Luo S, Meinel FG, McQuiston AD, Zhou CS, Kong X, Zhao YE, Zheng L, Schoepf UJ, Zhang LJ. High-pitch computed tomography pulmonary angiography with iterative reconstruction at 80 kVp and 20 mL contrast agent volume. Eur Radiol 2014; 24:3260-8. [PMID: 25100336 DOI: 10.1007/s00330-014-3365-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 05/12/2014] [Accepted: 07/21/2014] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To evaluate the image quality, radiation dose and diagnostic accuracy of 80kVp, high-pitch CT pulmonary angiography (CTPA) with iterative reconstruction using 20 ml of contrast agent. METHODS One hundred patients with suspected pulmonary embolism (PE) were randomly divided into two groups (n = 50 each; group A, 100 kVp, 1.2 pitch, 60 ml of contrast medium and filtered back projection algorithm; group B, 80 kVp, 2.2 pitch, 20 ml of contrast medium and sinogram affirmed iterative reconstruction). Image quality, diagnostic accuracy and radiation dose were evaluated and compared. RESULTS Mean CT numbers of pulmonary arteries in group B were higher than those in group A (all P < 0.001). Contrast-to-noise ratio and signal-to-noise ratio of group B were higher than those of group A (both P < 0.001). There was no significant difference in subjective image quality scores between two groups (P = 0.807). The interobserver agreement was excellent (k = 0.836). There was no significant difference in diagnostic accuracy between the two groups (P > 0.05). Compared with group A, radiation dose of group B was reduced by 50.3% (P < 0.001). CONCLUSIONS High-pitch CTPA at 80 kVp can obtain sufficient image quality in normal-weight individuals with 20 ml of contrast agent and half the radiation dose of a conventional CTPA protocol. KEY POINTS CTPA is feasible at 80 kVp using only 20 ml of contrast agent. High-pitch CTPA at 80 kVp has an effective dose under 1 mSv. This CTPA protocol can obtain sufficient image quality in normal-weight individuals.
Collapse
Affiliation(s)
- Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China,
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Zizka J, Ryska P, Stepanovska J, Poulova Z, Klzo L, Grepl J, Cermakova E. Iterative reconstruction of pulmonary MDCT angiography: Effects on image quality, effective dose and estimated organ dose to the breast. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2014; 158:259-64. [DOI: 10.5507/bp.2013.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Accepted: 07/25/2013] [Indexed: 11/23/2022] Open
|
38
|
John G, Marti C, Poletti PA, Perrier A. Hemodynamic indexes derived from computed tomography angiography to predict pulmonary embolism related mortality. BIOMED RESEARCH INTERNATIONAL 2014; 2014:363756. [PMID: 25147798 PMCID: PMC4087299 DOI: 10.1155/2014/363756] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/02/2014] [Indexed: 12/05/2022]
Abstract
Pulmonary embolism (PE) induces an acute increase in the right ventricle afterload that can lead to right-ventricular dysfunction (RVD) and eventually to circulatory collapse. Hemodynamic status and presence of RVD are important determinants of adverse outcomes in acute PE. Technologic progress allows computed tomography angiography (CTA) to give more information than accurate diagnosis of PE. It may also provide an insight into hemodynamics and right-ventricular function. Proximal localization of emboli, reflux of contrast medium to the hepatic veins, and right-to-left short-axis ventricular diameter ratio seem to be the most relevant CTA predictors of 30-day mortality. These elements require little postprocessing time, an advantage in the emergency room. We herein review the prognostic value of RVD and other CTA mortality predictors for patients with acute PE.
Collapse
Affiliation(s)
- Gregor John
- Department of Internal Medicine, Rehabilitation and Geriatrics, Geneva University Hospitals (HUG), Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland
| | - Christophe Marti
- Department of Internal Medicine, Rehabilitation and Geriatrics, Geneva University Hospitals (HUG), Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland
| | - Pierre-Alexandre Poletti
- Department of Radiology, Emergency-Room Radiology Unit, Geneva University Hospitals (HUG), Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland
| | - Arnaud Perrier
- Department of Internal Medicine, Rehabilitation and Geriatrics, Geneva University Hospitals (HUG) and Geneva Faculty of Medicine, Gabrielle-Perret-Gentil 4, 1211 Geneva, Switzerland
| |
Collapse
|
39
|
Beitzke D, Nolz R, Unterhumer S, Plank C, Weber M, Schernthaner R, Schöpf V, Wolf F, Loewe C. Low-dose high-pitch CT angiography of the supraaortic arteries using sinogram-affirmed iterative reconstruction. PLoS One 2014; 9:e99832. [PMID: 24919195 PMCID: PMC4053523 DOI: 10.1371/journal.pone.0099832] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 05/19/2014] [Indexed: 11/18/2022] Open
Abstract
Objective To prospectively evaluate image quality and radiation dose using a low-dose computed tomography angiography protocol and iterative image reconstruction for high-pitch dual-source CT-angiography (DSCTA) of the supraaortic arteries. Material and Methods DSCTA was performed in 42 patients, using either 120 kVp tube voltage, 120 mAS tube current, 2.4 pitch and filtered back projection, or 100 kVp tube voltage, 100 mAs tube current, 3.2 pitch, and sinogram affirmed iterative reconstruction. Measurements of vessel attenuation, of the contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) were performed to objectively evaluate image quality. Two readers evaluated subjective image quality and image noise, using a four-point scale. Effective dose was used to compare the differences in radiation dose. Results Low-dose protocol application showed significantly higher vessel opacification (p = 0.013), and non-significantly higher CNR and SNR values. There was no difference in the subjective image quality and image noise reading between the protocols. Effective dose was significantly lower using the low-dose protocol (1.29±0.21 mSv vs. 2.92±0.72 mSv; p<0.001). Conclusion The combined use of reduced tube voltage, reduced tube current, and iterative reconstruction reduces radiation dose by 55.4% in high-pitch DSCTA of the supraaortic arteries without impairment of image quality.
Collapse
Affiliation(s)
- Dietrich Beitzke
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
- * E-mail:
| | - Richard Nolz
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| | - Sylvia Unterhumer
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| | - Christina Plank
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| | - Michael Weber
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| | - Rüdiger Schernthaner
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| | - Veronika Schöpf
- Department of Biomedical Imaging and Image-guided Therapy, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Vienna, Austria
| | - Florian Wolf
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| | - Christian Loewe
- Department of Biomedical Imaging and Image-guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University Vienna, Vienna, Austria
| |
Collapse
|
40
|
Qi L, Meinel FG, Zhou CS, Zhao YE, Schoepf UJ, Zhang LJ, Lu GM. Image quality and radiation dose of lower extremity CT angiography using 70 kVp, high pitch acquisition and sinogram-affirmed iterative reconstruction. PLoS One 2014; 9:e99112. [PMID: 24915439 PMCID: PMC4051648 DOI: 10.1371/journal.pone.0099112] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/10/2014] [Indexed: 01/09/2023] Open
Abstract
Objectives The purpose of this study was to assess image quality and radiation dose of lower extremity CT angiography (CTA) with 70 kVp, high pitch acquisition and sinogram-affirmed iterative reconstruction (SAFIRE). Methods Lower extremity CTAs were performed on 44 patients: 22 patients were examined using protocol A (120 kVp, pitch of 0.85 and 120 ml of contrast agent on a first-generation dual-source CT) (120 kVp group) and 22 patients were evaluated with protocol B (70 kVp, pitch of 2.2 and 80 ml of contrast agent on a second-generation dual-source CT) (70 kVp group). Images from the 120 kVp group were reconstructed with filtered back projection (FBP) and images from the 70 kVp group with SAFIRE. The attenuation, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Two radiologists subjectively assessed image quality of lower extremity arteries, plantar arterial enhancement and venous contamination of all patients. Radiation dose was compared between the two groups. Results Higher mean intravascular attenuation was obtained in the 70 kVp group (70 vs. 120 kVp group, 555.4±83.4 HU vs. 300.9±81.4 HU, P<0.001), as well as image noise (20.0±2.8 HU vs. 17.5±3.2 HU, P = 0.010), SNR (32.0±7.0 vs. 19.1±6.9, P<0.001) and CNR (28.1±6.6 vs 15.9±6.3, P<0.001). No difference in subjective image quality and plantar arterial enhancement was found between 120 kVp group and 70 kVp group (all P>0.05). The venous contamination score was 1.5±0.8 for 120 kVp group while no venous contamination was found in 70 kVp group. The inter-observer agreement was moderate to good for both groups (0.515∼1, P<0.001). The effective dose was lower in 70 kVp group (0.3±0.1 mSv) than in 120 kVp group (1.6±0.7 mSv)(P<0.001). Conclusions Lower extremity CTA using 70 kVp, high pitch acquisition and SAFIRE, except increasing imaging noise, allows for lower radiation dose and contrast material volume without compromising image quality.
Collapse
Affiliation(s)
- Li Qi
- Department of Medical Imaging, Jinling Hospital, Clinical School of South Medical University, Nanjing, Jiangsu, China
| | - Felix G. Meinel
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Chang Sheng Zhou
- Department of Medical Imaging, Jinling Hospital, Clinical School of South Medical University, Nanjing, Jiangsu, China
| | - Yan E. Zhao
- Department of Medical Imaging, Jinling Hospital, Clinical School of South Medical University, Nanjing, Jiangsu, China
| | - U. Joseph Schoepf
- Department of Medical Imaging, Jinling Hospital, Clinical School of South Medical University, Nanjing, Jiangsu, China
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Clinical School of South Medical University, Nanjing, Jiangsu, China
- * E-mail: (LJZ); (GML)
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Clinical School of South Medical University, Nanjing, Jiangsu, China
- * E-mail: (LJZ); (GML)
| |
Collapse
|
41
|
Dual-energy computed tomography for the assessment of early treatment effects of regorafenib in a preclinical tumor model: comparison with dynamic contrast-enhanced CT and conventional contrast-enhanced single-energy CT. Eur Radiol 2014; 24:1896-905. [PMID: 24871332 DOI: 10.1007/s00330-014-3193-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 04/05/2014] [Accepted: 04/15/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The potential diagnostic value of dual-energy computed tomography (DE-CT) compared to dynamic contrast-enhanced CT (DCE-CT) and conventional contrast-enhanced CT (CE-CT) in the assessment of early regorafenib treatment effects was evaluated in a preclinical setting. METHODS A rat GS9L glioma model was examined with contrast-enhanced dynamic DE-CT measurements (80 kV/140 kV) for 4 min before and on days 1 and 4 after the start of daily regorafenib or placebo treatment. Tumour time-density curves (0-240 s, 80 kV), DE-CT (60 s) derived iodine maps and the DCE-CT (0-30 s, 80 kV) based parameters blood flow (BF), blood volume (BV) and permeability (PMB) were calculated and compared to conventional CE-CT (60 s, 80 kV). RESULTS The regorafenib group showed a marked decrease in the tumour time-density curve, a significantly lower iodine concentration and a significantly lower PMB on day 1 and 4 compared to baseline, which was not observed for the placebo group. CE-CT showed a significant decrease in tumour density on day 4 but not on day 1. The DE-CT-derived iodine concentrations correlated with PMB and BV but not with BF. CONCLUSIONS DE-CT allows early treatment monitoring, which correlates with DCE-CT. Superior performance was observed compared to single-energy CE-CT. KEY POINTS • Regorafenib treatment response was evaluated by CT in a rat tumour model. • Dual-energy contrast-enhanced CT allows early treatment monitoring of targeted anti-tumour therapies. • Dual-energy CT showed higher diagnostic potential than conventional contrast enhanced single-energy CT. • Dual-energy CT showed diagnostic potential comparable to dynamic contrast-enhanced CT. • Dual-energy CT is a promising method for efficient clinical treatment response evaluation.
Collapse
|
42
|
Del Gaizo AJ, Silva AC, Hara AK. The utility of dual-energy computed tomography in abdominal imaging. APPLIED RADIOLOGY 2014. [DOI: 10.37549/ar2048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
43
|
Chen Y, Xue H, Jin ZY, Zhang J, Sun H, Wang X, Zhang ZH, Zhang DM, Lu GM, Zhang ZQ, Schoepf UJ, Bucher AM, Wolla CD, Wang Y. 128-slice acceletated-pitch dual energy CT angiography of the head and neck: comparison of different low contrast medium volumes. PLoS One 2013; 8:e80939. [PMID: 24260516 PMCID: PMC3834309 DOI: 10.1371/journal.pone.0080939] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 10/08/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Our study aims to evaluate the image quality and feasibility of 128-slice dual-energy CTA (DE-CTA) for supra-aortic arteries using reduced amounts of contrast medium (CM). METHODS A prospective study was performed in 54 patients receiving CTA of the head and neck with a 128-slice dual-source CT system. Patients were randomized into two groups with a volume of either 40 mL of CM (Group I) or 50 mL of CM (Group II). Arterial and venous enhancements were recorded for quantitative assessment. Qualitative assessments for images without bone removal (BR) were based on a) the visualization of the circle of Willis and b) streak artifacts due to residual CM in the subclavian or internal jugular veins ipsilateral to injection of CM. Qualitative assessment of dual-energy images using BR was based on the presence of bone remnants and vessel integrity. Quantitative data was compared using the Student t test. The χ(2) test was used for the qualitative measurements of streak artifacts in veins while the Mann-Whitney U test was used for the qualitative measurements of images with BR. RESULTS Arterial and venous attenuation was significantly higher in Group II (P=0.000). Image quality regarding the circle of Willis was excellent in both groups (3.90±0.30 for Group I and 4.00±0 for Group II) . Imaging of the internal jugular veins was scored higher in Group I (1.87±0.72) compared with Group II (1.48±0.51) (P=0.021). Within Group I using BR, mean scores for bone remnants did not differ significantly (P>0.05) but mean scores of vessel integrity (P<0.05) did. CONCLUSIONS Contrast-enhanced head and neck CTA is feasible using a scan protocol with low amounts of contrast medium (40 mL) on a 128-slice dual-energy CTA. The 40-mL protocol provides satisfactory image quality before and after dual-energy bone-removal post-processing.
Collapse
Affiliation(s)
- Yu Chen
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Huadan Xue
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- * E-mail: (HX); (ZYJ)
| | - Zheng-yu Jin
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- * E-mail: (HX); (ZYJ)
| | - Jie Zhang
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Hao Sun
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Xuan Wang
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Zhu-hua Zhang
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Da-ming Zhang
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Guang-ming Lu
- Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, Nanjing, Jiangsu, China
| | - Zhao-qi Zhang
- Department of Radiology, Beijing Institute of Heart, Lung and Blood Vessel Diseases and Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - U. Joseph Schoepf
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Andreas M. Bucher
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Christopher D. Wolla
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Yun Wang
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| |
Collapse
|
44
|
The Emergence of Ultra-Low–Dose Computed Tomography and the Impending Obsolescence of the Plain Radiograph? Can Assoc Radiol J 2013; 64:314-8. [DOI: 10.1016/j.carj.2013.09.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 09/25/2013] [Indexed: 11/23/2022] Open
|
45
|
Hou DJ, Tso DK, Davison C, Inacio J, Louis LJ, Nicolaou S, Reimann AJ. Clinical utility of ultra high pitch dual source thoracic CT imaging of acute pulmonary embolism in the emergency department: Are we one step closer towards a non-gated triple rule out? Eur J Radiol 2013; 82:1793-8. [DOI: 10.1016/j.ejrad.2013.05.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 04/30/2013] [Accepted: 05/03/2013] [Indexed: 11/28/2022]
|
46
|
Second-generation dual-energy computed tomography of the abdomen: radiation dose comparison with 64- and 128-row single-energy acquisition. J Comput Assist Tomogr 2013; 37:543-6. [PMID: 23863529 DOI: 10.1097/rct.0b013e318291f6a0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE This study was designed to compare the radiation dose in abdominal dual-energy (DE) and single-energy (SE) acquisitions obtained in clinical practice with a second-generation DE computed tomography (DECT) and to analyze the dose variation in comparison with an SE acquisition performed with a 64-row SECT (SECT). METHODS A total of 130 patients divided into 2 groups underwent precontrast and portal abdominal 128-row CT examination. In group A, DE portal acquisition was performed using a detector configuration of 2 × 40 × 0.6 mm, tube A at 80 kVp and a reference value of 559 mAs, tube B at 140 kVp and a reference value of 216 mAs, pitch 0.6, and online dose modulation; group B underwent SE portal acquisition using a detector configuration of 64 × 0.6 mm, 120 kVp and a reference value of 180 mAs, pitch 0.75, and online dose modulation. Group C consisted of 32 subjects from group A previously studied with 64-row SECT using the following parameters: detector configuration 64 × 0.6 mm, 120 kVp and a reference value of 180 mAs, pitch 0.75, and online dose modulation. In each group, the portal phase dose-length product and radiation dose (mSv) were calculated and normalized for a typical abdominal acquisition of 40 cm. RESULTS After normalization to standard 40-cm acquisition, a dose-length product of 599.0 ± 133.5 mGy · cm (range, 367.5 ± 1231.2 mGy · cm) in group A, 525.9 ± 139.2 mGy · cm (range, 215.7-882.8 mGy · cm) in group B, and 515.9 ± 111.3 mGy · cm (range, 305.5-687.2 mGy · cm) in group C was calculated for portal phase acquisition.A significant radiation dose increase (P < 0.05) was observed in group A (10.2 ± 2.3 mSv) compared with group B (8.9 ± 2.4) and group C (8.8 ± 1.9 mSv). No significant difference (P > 0.05) was reported between SE 64- and 128-row acquisitions. A significant positive correlation between radiation dose and body mass index was observed in each group (group A, r = 0.59, P < 0.0001; group B, r = 0.35, P < 0.0001; group C, r = 0.20, P = 0.0098). CONCLUSIONS In clinical practice, abdominal DECT acquisition shows a significant but minimal radiation dose increase, on the order of 1 mSv, compared with 64- and 128-row SE acquisition. The slightly increased radiation dose can be justified if the additional information obtained using a spectral imaging approach directly impacts on patient management or reduce the overall radiation dose with the generation of virtual unenhanced images, which can replace the precontrast acquisition.
Collapse
|
47
|
Co SJ, Mayo J, Liang T, Krzymyk K, Yousefi M, Nicolaou S. Iterative reconstructed ultra high pitch CT pulmonary angiography with cardiac bowtie-shaped filter in the acute setting: effect on dose and image quality. Eur J Radiol 2013; 82:1571-6. [PMID: 23777744 DOI: 10.1016/j.ejrad.2013.04.043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Revised: 04/22/2013] [Accepted: 04/22/2013] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the effect of a cardiac bowtie-shaped filter in an ultra high pitch CTPA protocol at 100 kV on image quality and radiation dose. MATERIALS AND METHODS Retrospective study of 100 patients referred for CTPA. 50 patients scanned with a standard 100 kV protocol at pitch 2.8 (Protocol A) and 50 patients scanned with a 100 kV protocol at pitch 3.2 with a cardiac bowtie-shaped filter (Protocol B). All other scanning parameters kept constant. Images from both groups reconstructed with filtered back projection and iterative reconstruction. Central pulmonary vessel attenuation and background noise were quantitatively measured and signal-to-noise (SNR) and contrast-to-noise (CNR) were calculated. Two radiologists performed qualitative assessment grading visualization of the pulmonary vasculature and noise level. CTDIvol and DLP were recorded and effective dose was calculated. RESULTS CTDIvol, DLP and effective dose were significantly (p<0.0001) lower in Protocol B (2.3 ± 0.5 mGy, 78.4 ± 16.5 mGycm, 1.4 ± 0.3 mSy, respectively) compared to Protocol A (4.3 ± 0.5 mGy, 152.0 ± 19.6 mGycm, 2.7 ± 0.3 mSy, respectively). Protocol B had significantly (p<0.0001) higher noise than Protocol A (23.8 ± 6.9 HU vs 36.8 ± 7.3 HU) and lower SNR (11.8 ± 3.7 HU vs 19.2 ± 8.1 HU) and CNR (10.3 ± 3.7 HU vs 24.9 ± 13.4 HU) but there was no significant difference in the subjective visualization of the pulmonary vasculature (p=0.63). Furthermore, iterative reconstruction significantly (p<0.0001) improves image noise (29.4 ± 5.5 HU from 36.8 ± 7.3 HU). CONCLUSION The addition of a cardiac bowtie-shaped filter with an ultra high pitch CTPA protocol at 100 kV resulted in a 48% dose reduction without significantly affecting diagnostic image quality. In addition, the use of iterative reconstruction significantly improves image quality by reducing noise permitting the possibility for further dose reduction strategies.
Collapse
Affiliation(s)
- Steven J Co
- Vancouver General Hospital, Department of Radiology, Jim Pattison Pavilion South, 899 West 12th Ave. Room G861, Vancouver BC V5Z 1M9, Canada.
| | | | | | | | | | | |
Collapse
|
48
|
Saade C, Bourne R, El-Merhi F, Somanathan A, Chakraborty D, Brennan P. An optimised patient-specific approach to administration of contrast agent for CT pulmonary angiography. Eur Radiol 2013; 23:3205-12. [DOI: 10.1007/s00330-013-2919-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2013] [Revised: 04/27/2013] [Accepted: 04/30/2013] [Indexed: 11/29/2022]
|
49
|
Cao LX, Zhang H, Liu B, Yang WJ, Zhang YY, Pan ZL, Yan FH, Chen KM. Evaluation of high-pitch flash scan for pulmonary venous CTA on a 128-slice dual source CT: compared with prospective ECG-triggered sequence scan. Int J Cardiovasc Imaging 2013; 29:1557-64. [PMID: 23645131 DOI: 10.1007/s10554-013-0227-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 04/19/2013] [Indexed: 11/30/2022]
Abstract
To compare the image quality (IQ) and radiation dose of high-pitch scan and prospective ECG-triggered sequence scan on a 128-slice DSCT system for patients with atrial fibrillation (AF). Pulmonary venous (PV) CTA was performed with two protocols, including high-pitch scan and prospective ECG-triggered sequence scan. For each protocol, 20 sex, age and body-mass-index (mean 24.2 kg/m(2)) matched patients were identified. Two experienced radiologists, who were blinded to the scan protocols, independently graded the CT images of the two groups by a 5-point scale for subjective IQ assessment. Measured CT attenuation (Hounsfield units ± standard deviation), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) at various anatomic locations were also recorded for objective IQ evaluation. Radiation exposure parameters [dose length product (DLP) and effective radiation dose (ERD)] were compared. Twenty-three patients (57.5 %) showed an ECG pattern of AF in total. Subjective IQ was rated excellent in 100 % for the high-pitch scan group, while minor step artifacts were observed in two patients (10 %) with arrhythmia for the prospective ECG-triggered sequence group. There was no significant difference on IQ, neither by subjective, nor by objective measures (SNR, CNR) between the two groups. The ERD of high-pitch flash scan and prospective ECG-triggered sequence scan were 0.9 (± 0.25) and 2.9 (± 0.69) mSv, respectively. Significantly lower radiation was achieved by using high-pitch flash scan (P < 0.05). High-pitch flash scan can provide similar subjective and objective IQ compared with prospective ECG-triggered sequence scan for PV CTA, while radiation exposure was significantly reduced.
Collapse
Affiliation(s)
- Li Xiu Cao
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University of Medicine, Shanghai, China
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Paul J, Mbalisike EC, Nour-Eldin NEA, Vogl TJ. Dual-source 128-slice MDCT neck: Radiation dose and image quality estimation of three different protocols. Eur J Radiol 2013; 82:787-96. [DOI: 10.1016/j.ejrad.2012.11.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 09/13/2012] [Accepted: 11/20/2012] [Indexed: 10/27/2022]
|